The present invention relates to compositions related to proteins which function in controlling physiology, development, and/or differentiation of mammalian cells. In particular, it provides proteins which are implicated in the regulation of physiology, development, differentiation, or function of various cell types, e.g., chemokines, 7 transmembrane receptors, reagents related to each, e.g., antibodies or nucleic acids encoding them, and uses thereof. It also provides methods of using various chemokine compositions, and compositions used for such, and more particularly, to methods of treating skin diseases or conditions associated with misregulation of the chemokines CTACK and/or CTACK.
The immune system consists of a wide range of distinct cell types, each with important roles to play. See Paul (ed. 1997) Fundamental Immunology 4th ed., Raven Press, New York. The lymphocytes occupy central stage because they are the cells that determine the specificity of immunity, and it is their response that orchestrates the effector limbs of the immune system. Two broad classes of lymphocytes are recognized: the B lymphocytes, which are precursors of antibody secreting cells, and the T (thymus-dependent) lymphocytes. T lymphocytes express important regulatory functions, such as the ability to help or inhibit the development of specific types of immune response, including antibody production and increased microbicidal activity of macrophages. Other T lymphocytes are involved in direct effector functions, such as the lysis of virus infected-cells or certain neoplastic cells.
The chemokines are a large and diverse superfamily of proteins. The superfamily is subdivided into two classical branches, based upon whether the first two cysteines in the chemokine motif are adjacent (termed the xe2x80x9cCxe2x80x94Cxe2x80x9d branch), or spaced by an intervening residue (xe2x80x9cC-X-Cxe2x80x9d). A more recently identified branch of chemokines lacks two cysteines in the corresponding motif, and is represented by the chemokines known as lymphotactins. Another recently identified branch has three intervening residues between the two cysteines, e.g., CX3C chemokines. See, e.g., Schall and Bacon (1994) Current Opinion in Immunology 6:865-873; and Bacon and Schall (1996) Int. Arch. Allergy and Immunol. 109:97-109.
Many factors have been identified which influence the differentiation process of precursor cells, or regulate the physiology or migration properties of specific cell types. These observations indicate that other factors exist whose functions in immune function were heretofore unrecognized. These factors provide for biological activities whose spectra of effects may be distinct from known differentiation or activation factors. The absence of knowledge about the structural, biological, and physiological properties of the regulatory factors which regulate cell physiology in vivo prevents the modulation of the effects of such factors. Thus, medical conditions where regulation of the development or physiology of relevant cells is required remain unmanageable.
The present invention is based, in part, upon the discovery of various chemokine binding partners for 7 transmembrane receptors, and upon the surprising discovery that the CTACK and Vic chemokines are expressed on skin cells. They have been shown to have effects on immune cells related to dermatological health.
The present invention provides, e.g., methods of modulating movement of a cell within or to the skin of a mammal, the method comprising administering to the mammal an effective amount of: an antagonist of CTACK; an agonist of CTACK; an antagonist of Vic; or an agonist of Vic. Often, in the method, the modulating is blocking and the administering is an antagonist of CTACK or Vic, e.g., wherein: the movement is: within the skin, chemotactic, or chemokinetic; the administering is local, topical, systemic, subcutaneous, intradermal, or transdermal; the administering is an antagonist of CTACK or Vic; the cell is a CLA+ cell, a T cell, a dendritic cell, or a dendritic cell precursor; a dermal fibroblast; a deraml endothelial cell, or a melanocyte; or the cell moves into the dermis and/or epidermis layers of the skin. Particularly, such method will be one wherein: the antagonist is selected from a mutein of natural CTACK or Vic, an antibody which neutralizes CTACK or Vic, or an antibody which blocks GPR2 ligand binding; the mammal is subject to a transplant or skin graft; or the antagonist is administered in combination with an antibiotic, analgesic, immune suppressive therapeutic, anti-inflammatory drug, growth factor, or immune adjuvant.
In other methods, the modulating is attracting and the administering is an agonist of CTACK or Vic. In certain embodiments, the movement is: within the skin, chemotactic, or chemokinetic; the administering is local, topical, subcutaneous, intradermal, or transdermal; the administering is a CTACK or Vic ligand; the cell is a CLA+ cell, a T cell, a dendritic cell, or a dendritic cell precursor; a dermal fibroblast, a dermal endothelial cell, or a melanocyte; or the cell moves into the dermis and/or epidermis layers of the skin. Certain preferred methods will be where the agonist is selected from CTACK or Vic, or a GPR2 ligand; the mammal is subject to a cutaneous lesion; or the agonist is administered in combination with an antibiotic, analgesic, immune suppressive therapeutic, anti-inflammatory drug, growth factor, or immune adjuvant. The agonist is also adminisitered as a cutaneous adjuvant alone.
Other aspects of the invention include methods of purifying a population of cells, the method comprising contacting the cells with CTACK or Vic, thereby resulting in the identification of cells expressing a receptor for the CTACK or Vic. Particular forms include wherein the contacting results in specific movement of the cells to a site for purification, e.g., through pores of a membrane.
The invention also provides methods of producing a ligand:receptor complex, comprising contacting: a mammalian CTACK with a GPR2 receptor; or a mammalian Vic with a GPR2 receptor; wherein at least one of the ligand or receptor is recombinant or purified, thereby allowing the complex to form. In such methods are included those wherein: the complex results in a Ca++ flux; the GPR2 receptor is on a cell; the complex formation results in a physiological change in the cell expressing the GPR2 receptor; the contacting is in combination with IL-2 and/or interferon-xcex1; or the contacting allows quantitative detection of the ligand.
Additionally, the invention teaches methods of modulating physiology or development of a GPR2 expressing cell comprising contacting the cell to an agonist or antagonist of a mammalian Vic or CTACK, wherein one of the GPR2 receptor or the agonist or antagonist is recombinant or purified. This will include where: the antagonist is: an antibody which: neutralizes the mammalian Vic, neutralizes the mammalian CTACK, or blocks ligand binding by GPR2; or a mutein of the Vic or CTACK; or the physiology is selected from: a cellular calcium flux; a chemoattractant response; a cellular morphology modification response; phosphoinositide lipid turnover; or an antiviral response. Within such methods are where: the antagonist is an antibody and the physiology is a chemoattractant response; or the modulating is blocking, and the physiology is an inflammatory response.
Testing methods are provided, e.g., testing a compound for ability to affect GPR2 receptor-ligand interaction, the method comprising comparing the interaction of GPR2 with Vic or CTACK in the presence and absence of the compound. Among such methods are those wherein the compound is an antibody against GPR2, Vic, or CTACK.
Various GPR2 compositions are also provided, e.g., a primate GPR2, comprising sequence of MGTEVLEQ (see SEQ ID NO: 2); a nucleic acid encoding the GPR2; or an antibody which binds selectively to MGTEVLEQ (see SEQ ID NO: 2).
Also provided is a method of treating a patient suffering from a skin disorder comprising administering an effective amount of an antagonist against GPR2, Vic, or CTACK. The method further provides an antagonist which is an antibody.